Improvement in safety-valves for steam-generators



UNITED STATES PATENT OFFICE.

ROBERT MOOD, OF INDIANAPOLIS, INDIANA.

IMPROVEMENT IN SAFETY-VALVES FOR STEAM-GENERATORS.

Speeication forming part of Letters Patent No. 50,376, dated October 10,1865.

To all whom it may concern:

Beit known that I, ROBERT MOOD, of Indianapolis, in the State ofIndiana, havein vented acertain new and useful Safety-Valve Arrangementfor Steam-Boilers; and I do hereby decla-re that the following is afull, clear, and exact description thereof', reference being had to theaccompanyingdrawings, and to the letters and marks thereon.

My invention has for its object an arrangementofsai'ety-wal ves forstcam-boilers,together with the means for controlling the operationthereof, which shall be entirely under the control ofthe inspectors ormanaging ocers, (they determining the exact pressure of stean1,)and notliable to be tampered with by the engineman or others, or the pressureof stearn allowed to be increased beyond the degree to which theapparatus may be iixed by the inspector or managing officer.

The drawings forming part of this specification show how niy inventionmay be carried out, Figure l of these drawings being a view in elevationof the chamber or case containing the apparatus, and Fig. 2 beinga Viewby vertical section through the center of the appa-4 rains.

In both of these figures, where like parts are shown like marks andletters are used to indicate the parts.

Upon the cap a of the steam-chamber b, or upon such other part of thesteam-space of the boiler as may be preferred, and over or in suitablevalve-seats, c, therein or thereon, Iplace two valves, d d, as isindicated by Fig. 2 ofthe drawings. A lever, c, having two screws,ff,lies above the valves, each screw respectively pressing upon the centerof each valve, the endsoi' the screws bearing in suitable recesses onthe upper surfaces of the valves. Above the bearing portion of the leveris a spring, g, which may be of the shape shown, or may be a volute,spiral, or any other suitable form. Above the spring is a cross-bar, h,made so as to slide in guide-bars i t; and above the crossbar is aneceentric,j, having suitable bearings for its shaft lo in theguide-bars, which crossbar and eccentric may be connected to each otherby the usual or ordinary strap. The pressure of the eccentric throughthe bar upon the spring may be made by the use ofa toothed lever, wheel,gearing, and screws, either coulbined or by such pieces or parts thereofas will answer to regulate the pressure of the eccentric and hohl it inthe position desired.

A cap or cover, l, will be placed over the apparatus and so secured tothe case or chamber that the pieces or parts of the apparatus cannot betampered with.

The greatest degree of pressure that can be exerted on the valves willbe that occurring when the eccentric is at its greatest degree ofeccentricity, oratits full throw, and thus, while I a lesser pressuremay be that fixed upon, and which cannot without violence be changed,except by the proper officer having charge of the key locking the cap,an excess over the greatest degree of eccentrieity can never be created.A safe pressure can therefore always be secured by the proper adaptationof size or diameter of the eccentric used. The screws ff in the leverwill be useful, also, in adjusting the pressure on the valves. Pressuremade upon the handle of the lever e will allow of the trying of the onevalve, while the lifting up of the end of the lever will admit thetrying of the other valve; but, as will be perceived, the lever cannotbe made use of to increase the pressure upon both of the valves at thesame time.

The guide-bars t' 'i will serve as guides to the spring as well as tothe bar and the other pieces.

What I claim as my invention, and desire to secure by Letters Patent,is-

The arrangementof the valves, lever, spring, and cross-bar with theeccentric, substantially as herein set forth.

This specification signed this 26th day of August, 1865.

ROBERT MOOD. Witnesses:

WALTER S. PHELPS, J. MILNER.

